RAF ONCOGENE ANALYSIS AND RADIATION RESISTANT TUMOR CELL

对相关基因变化的因果关系的探索 肿瘤细胞在癌症研究中占据中心位置。 一年半前，我们开始解决可能的原因 一种人类喉癌。我们现在已经报道了该协会 一个异常的RAF癌基因与抗辐射的人类 喉癌细胞系SQ-20B。我们的研究一直是 补充了在另一份报告中提出的独立意见 实验室认为非癌症、抗辐射的皮肤成纤维细胞 有抗辐射家族史的患者 恶性肿瘤显示了一种异常的RAF癌基因。然而，这些 有两份报告尚未证明这一点的确切性质 异常，也不与靶细胞对 辐射毒性。 在这一授权期内，我们的主要目标是 RAF基因表达调控与细胞周期调控的研究 对辐射损害的反应 正义或反义RAF的最佳表达以适当的 哺乳动物细胞(AIM I)，解剖和表征RAF SQ-20B细胞的癌基因结构和功能(AIM II)，以及 在另外三个密切关注的地方寻找基因异常 相关人类癌症(AIM III)。 我们将使用明确、可行和综合的方法来 评价SQ-RAF功能障碍的遗传基础 200b细胞。可获得性极大地促进了这些研究 克隆并定义了含有人的独特表达载体 RAF(正义/反义)序列、c-raf-1 DNA探针、核探针 适合RAF(反义+)分析的载体探针，以及 抗RAF蛋白的抗体来自乔治·马克博士(NIH)。我们会 保持我们与Anatoly博士的持续合作 Dritschilo，George Mark和Michael Gottesman为他们的 放射生物学、分子生物学领域的专门知识 以及多药耐药的分子生物学， 分别进行了分析。最后，目前的调查应该会引导我们 开始阐明RAF原的结构和功能- 癌基因结构域对正常细胞的维持至关重要 扩散和行为。

The search for the cause and effect of genetic changes associated with neoplastic cells occupies a central place in cancer research. A year and a half ago, we began to address the possible causes of a human laryngeal cancer. We have now reported the association of an abnormal RAF oncogene with a radiation resistant human laryngeal carcinoma cell line, SQ-20B. Our studies have been complemented by the independent observations made in another laboratory that noncancerous, radiation resistant skin fibroblasts of patients with a familial history of radiation resistant malignancies reveal an abnormal RAF oncogene. However, these two reports have not yet proven the precise nature of this abnormality, nor its relevance to the resistance of target cells to radiation toxicity. Our major gaols during the tenure of this grant period will be to study the modulation of RAF gene expression and the cellular responses to radiation-damage as a consequence of delivering an optimal expression of sense or anti-sense RAF to the appropriate mammalian cells (AIM I), to dissect and characterize the RAF oncogene structure and function in SQ-20B cells (AIM II), and to search for genetic abnormalities in three additional closely related human cancers (AIM III). We will use a clearly defined, feasible, and integrated approach to evaluate the genetic basis of malfunctioning of the RAF in SQ- 20B cells. These studies are greatly facilitated by the availability of cloned and defined unique expression vectors containing human RAF(sense/anti-sense) sequence, c-RAF-1 DNA probes, riboprobe vector probes suitable for RAF (anti-sense+) analysis, and antibody to RAF protein from Dr. George Mark (NIH). We will maintain our ongoing collaborative efforts with Drs. Anatoly Dritschilo, George Mark, and Michael Gottesman for their specific expertise in the areas of radiobiology, molecular biology of RAF, and molecular biology of multidrug resistance, respectively. Finally, the current investigations should lead us to begin to elucidate the structure and function of RAF proto- oncogene domains pivotal to the maintenance of normal cell proliferation and behavior.